Last updated: June 2, 2025
Understanding the UV Index in Casper, United States is crucial for protecting your skin from harmful solar radiation. With summer sunshine peaking in the high desert climate of Casper, where the BSk climate brings clear skies and abundant sun, awareness of UV levels can help prevent sunburn and promote long-term skin health. During peak hours, the UV Index often reaches dangerous levels, emphasizing the importance of sun safety practices to minimize risks. Stay informed and enjoy the outdoors responsibly!
The UV Index throughout the day presents a fascinating pattern as the sun ascends. At 07:00, the index starts at a gentle 1, indicating minimal risk. However, by 09:00, it climbs to 4, marking the arrival of noticeable sunlight. The real intensity hits its peak at 12:00, soaring to an impressive 11—a cautionary moment for those outdoors. As we move through the afternoon, the index remains elevated, reaching 12 at 13:00 before gradually descending, settling back to 7 by 16:00. The evening sees a return to safer levels with 2 at 18:00 and finally back to 1 as the day wanes at 19:00. This dynamic shift underscores the importance of sun protection during peak hours, particularly from 10:00 to 14:00.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 7 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so do the UV Index levels, impacting sun exposure and burn times significantly. January begins with a moderate UV Index of 4 and a burn time of 30 minutes, but by April, the index escalates to an extreme level of 11, drastically reducing burn time to just 10 minutes. The highest risk months are June and July, featuring an extreme UV Index of 12 and a minimal burn time of 10 minutes, highlighting the need for caution. As summer transitions to fall, the UV Index begins to decline, with September at 9 (very high) and October back to 6 (high). November and December see moderate levels again with indices of 4 and 3 respectively, allowing for longer burn times of 30 minutes. It is essential for visitors and residents to remain vigilant during high-risk months (April through September), utilizing sunscreen, protective clothing, and limiting sun exposure during peak hours to ensure safety while enjoying the outdoors.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Casper | 4 | 6 | 7 | 11 | 10 | 12 | 12 | 11 | 9 | 6 | 4 | 3 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |